Abstract: Methods and systems are provided for controlling transitions between engine operating modes in a four-cylinder engine. One method includes transitioning engine operation between two-cylinder, three-cylinder, and four-cylinder modes wherein the transitioning includes a sequence of firing events such that successive firing events are separated by at least 120 crank angle degree intervals.

Abstract: A method includes spraying a coating on to an engine bore surface, honing the coated surface to create a honed surface region, and cleaning the honed surface region to remove material from the surface pores. The honed surface region includes a plurality of surface pores and upper, middle, and lower regions. Cleaning the honed surface region produces upper, middle, and lower region surface porosities, with the middle region porosity being greater than at least one of the upper and lower porosities.

Abstract: A method includes spraying a coating on to an engine bore surface, honing the coated surface to create a honed surface region, and cleaning the honed surface region to remove material from the surface pores. The honed surface region includes a plurality of surface pores and upper, middle, and lower regions. Cleaning the honed surface region produces upper, middle, and lower region surface porosities, with the middle region porosity being greater than at least one of the upper and lower porosities.

Abstract: Methods and systems are provided for operating an engine with variable displacement engine (VDE) operation coupled to a twin scroll turbocharger. One method comprises directing exhaust from a first outer cylinder and a first inner cylinder of four cylinders to a first scroll of the twin scroll turbocharger, directing exhaust from a second outer cylinder and a second inner cylinder of the four cylinders to a second scroll of the twin scroll turbocharger, and during a first condition, firing all four cylinders with uneven firing.

Abstract: Methods and systems are provided for controlling vibrations during transitions between engine operating modes in a four-cylinder engine. One method includes timing a transition in engine operation between two-cylinder, three-cylinder, and four-cylinder modes with a sequence of firing events such that successive firing events are separated by at least 120 crank angle degree intervals. Vibrations resulting from transitions may be countered by adjusting active mounts, the active mounts being adjusted in synchronization with a valvetrain switching solenoid.

Abstract: Methods and systems are provided for operating an engine with variable displacement engine (VDE) operation coupled to a twin scroll turbocharger. One method comprises directing exhaust from a first outer cylinder and a first inner cylinder of four cylinders to a first scroll of the twin scroll turbocharger, directing exhaust from a second outer cylinder and a second inner cylinder of the four cylinders to a second scroll of the twin scroll turbocharger, and during a first condition, firing all four cylinders with uneven firing.

Abstract: Methods and systems are provided for controlling transitions between engine operating modes in a four-cylinder engine. One method includes transitioning engine operation between two-cylinder, three-cylinder, and four-cylinder modes wherein the transitioning includes a sequence of firing events such that successive firing events are separated by at least 120 crank angle degree intervals.

Abstract: An engine includes a cylinder block defining at least one main bearing bulkhead adjacent to a cylinder, and a crankshaft rotatably housed within the block by a main bearing. A bulkhead insert has a cap portion, and an insert portion provided within the bulkhead. The insert portion has having first and second end regions connected by first and second straps. Each strap having a flanged beam cross section. The first and second ends of the insert portion are configured to connect a main bearing cap column to a cylinder head column. Each of the first and second end regions define at least one protrusion having a surface substantially normal to engine combustion and reactive loads. The cap portion is configured to mate with the first end region at the main bearing cap column and support the main bearing.

Abstract: Methods and systems are provided for operating an engine with variable displacement engine (VDE) operation coupled to a twin scroll turbocharger. One method comprises directing exhaust from a first outer cylinder and a first inner cylinder of four cylinders to a first scroll of the twin scroll turbocharger, directing exhaust from a second outer cylinder and a second inner cylinder of the four cylinders to a second scroll of the twin scroll turbocharger, and during a first condition, firing all four cylinders with uneven firing.

Abstract: A turbocharger is provided herein. The turbocharger includes a housing and an adjustable core at least partially circumferentially surrounded by the housing, the adjustable core having a turbine rotor coupled to a compressor rotor via a shaft. The turbocharger further includes an adjustment mechanism coupled to the adjustable core configured to adjust an axial position of the housing relative to the adjustable core in response to adjustment commands.

Abstract: Methods and systems are provided for controlling engine operation. One method comprises during a first condition, operating the engine with a single cylinder deactivated and remaining cylinders activated with a first intake duration, and during a second condition, operating the engine with the single cylinder deactivated and the remaining cylinders activated with a second intake duration. The method further comprises during a third condition, operating the engine with all cylinders activated.

Abstract: Methods and systems are provided for controlling transitions between engine operating modes in a four-cylinder engine. One method includes transitioning engine operation between two-cylinder, three-cylinder, and four-cylinder modes wherein the transitioning includes a sequence of firing events such that successive firing events are separated by at least 120 crank angle degree intervals.

Abstract: Systems and methods for increasing an amount of fuel injected into a dedicated exhaust gas recirculation (EGR) cylinder in an engine are disclosed. In one example approach, a method comprises, prior to combustion, injecting a first amount of fuel to a dedicated EGR cylinder, and after combustion and during an expansion and/or exhaust stroke, directly injecting a second amount of fuel to the dedicated EGR cylinder.

Abstract: Methods and systems are provided for varying a location and rate of EGR delivered to an engine from a dedicated EGR cylinder. The dedicated EGR cylinder is configured with a plurality of exhaust valves controlled via a cam profile switching mechanism that allows the time and duration of opening of each exhaust valve to be varied. By selectively opening one exhaust valve at a time, exhaust from the dedicated EGR cylinder can be delivered to a pre-compressor location, a post-compressor location, or to the exhaust manifold, while bypassing all engine cylinders.

Abstract: Methods and systems are provided for operating an engine with variable displacement engine (VDE) operation coupled to a twin scroll turbocharger. One method comprises directing exhaust from a first outer cylinder and a first inner cylinder of four cylinders to a first scroll of the twin scroll turbocharger, directing exhaust from a second outer cylinder and a second inner cylinder of the four cylinders to a second scroll of the twin scroll turbocharger, and during a first condition, firing all four cylinders with uneven firing.

Abstract: Various systems and methods are described for controlling engine operation. One method comprises, during a first variable displacement engine (VDE) mode in an engine having four cylinders, deactivating a first cylinder of the four cylinders and firing a second, third, and fourth cylinder of the four cylinders, each firing event separated by 240 degrees of crank angle (CA). The engine may be operated in a non-VDE mode by activating the first of the four cylinders and firing the first cylinder between the third and fourth cylinders.

Abstract: An engine includes a cylinder block defining at least one main bearing bulkhead adjacent to a cylinder, and a crankshaft rotatably housed within the block by a main bearing. A bulkhead insert has a cap portion, and an insert portion provided within the bulkhead. The insert portion has having first and second end regions connected by first and second straps. Each strap having a flanged beam cross section. The first and second ends of the insert portion are configured to connect a main bearing cap column to a cylinder head column. Each of the first and second end regions define at least one protrusion having a surface substantially normal to engine combustion and reactive loads. The cap portion is configured to mate with the first end region at the main bearing cap column and support the main bearing.

Abstract: Methods and systems are provided for operating an engine with variable displacement engine (VDE) operation coupled to a twin scroll turbocharger. One method comprises directing exhaust from a first outer cylinder and a first inner cylinder of four cylinders to a first scroll of the twin scroll turbocharger, directing exhaust from a second outer cylinder and a second inner cylinder of the four cylinders to a second scroll of the twin scroll turbocharger, and during a first condition, firing all four cylinders with uneven firing.

Abstract: Methods and systems are provided for controlling transitions between engine operating modes in a four-cylinder engine. One method includes transitioning engine operation between two-cylinder, three-cylinder, and four-cylinder modes wherein the transitioning includes a sequence of firing events such that successive firing events are separated by at least 120 crank angle degree intervals.

Abstract: Methods and systems are provided for controlling vibrations during transitions between engine operating modes in a four-cylinder engine. One method includes timing a transition in engine operation between two-cylinder, three-cylinder, and four-cylinder modes with a sequence of firing events such that successive firing events are separated by at least 120 crank angle degree intervals. Vibrations resulting from transitions may be countered by adjusting active mounts, the active mounts being adjusted in synchronization with a valvetrain switching solenoid.